SPRING CALULCATION IN MULTI PURPOSE CHECK VALVE 1

[skengg]

Hello to all,
before asking, let me first give you description about product, our company designing CAST SS 304 Multi purpose check valve (for both horizontal & vertical line) for pump application. i have already available sample of one size of valve.i noticed that spring in that sample valve has stiffness of very less value, with minor force spring touch to its solid length. so my question is, isn't general guidelines of designing spring is that we should keep its operational length should be less then solid length or there is something else?

 

[gerhardl]

For a spring operated check valve we are talking of a balance of correct forces, not length. The length, however, of a spring, dimensioned to give the correct force (both for closing and opening pressure), must be sufficient to give this force over the valves lifetime, natural weakening over dimensioned life-time considered. ??? Is this an answer to your question?

 

[skengg]

i got it, but the spring i have as sample,calculated stiffness of very less value, like with a minor touching force it gets huge deflection(almost reach to solid length). so i have query that isn't while designing spring, we should consider operational length less than solid length?

 

[gerhardl]

Hello again! Seems that you are asking a sensible question, where the answer is normally 'yes'. So why dont you simply ask the responsible person/persons the purpose of a shorter length?